Remove specification of user.* git config for docbuild and test CIs

[yarikoptic]

for tests we might need first a

• https://github.com/datalad/datalad-fuse/pull/113

Added a commit I recommended in that PR, so if works

• Closes #113
• Closes #112

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 91.02%. Comparing base (02200a1) to head (d9d60bc).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #114 +/- ## ======================================= Coverage 91.02% 91.02% ======================================= Files 10 10 Lines 624 624 ======================================= Hits 568 568 Misses 56 56 ```

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.

[yarikoptic]

benchmarks -- filed

• https://github.com/datalad/datalad-fuse/issues/115

otherwise -- green, thus merging